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Aqueous zinc‐ion batteries (ZIBs) are a promising candidate for fast‐charging energy‐storage systems due to its attractive ionic conductivity of water‐based electrolyte, high theoretical energy density, and low cost. Current strategies toward high‐rate ZIBs mainly focus on the improvement of ionic or electron conductivity within cathodes. However, enhancing intrinsic electrochemical reaction kinetics of active materials to achieve fast Zn2+ storage has been greatly omitted. Herein, for the first time, stable radical intermediate generation is demonstrated in a typical organic electrode material (methylene blue [MB]), which effectively decreases the reaction energy barrier and enhances the intrinsic kinetics of MB cathode, enabling ultrafast Zn2+ storage. Meanwhile, anionic co‐intercalation essentially avoids MB molecules rearranging their configuration and sharing Zn2+ with adjacent functional groups, thus keeps the structure stable. As a result, Zn–MB batteries exhibit an excellent rate capability up to 500C and ultralong life of 20 000 cycles with a negligible 0.07% capacity decay per cycle at 100C, which is superior to that of most reported aqueous ZIBs batteries. This work provides a novel strategy of stable radical chemistry for ultrafast‐charging aqueous ZIBs, which can be introduced to other appropriate organic materials and multivalent ion battery systems. [ABSTRACT FROM AUTHOR]

Desensitized energetic plasticizer (DEP) plays a crucial role in the properties of the binder, and thus can further influence the performances of desensitive Nitrate Ester Plasticized Polyether (NEPE) propellants, which represents the development direction of the next generation solid propellant composites. However, at present, a study on influencing mechanisms for curing properties of propellant binders at the atomic and molecular level was rarely reported. In the current study, based on the curing kinetics and mechanical properties of PET/N‐100 binder, the influencing mechanism of the DEPs, BDNPA/F, and Bu‐NENA, on the binder was determined by the Gaussian quantum chemical calculation and MD simulation at the chemical bond and polymer chain levels, as well as the characterizations of the curing network structure, glass transition temperature, and microphase separation of the binder system. The consistent results at both micro and macro levels offer important theoretical guidance for studying the structure‐mechanism‐performance relationship of propellant binder, as well as for exploring the strategies that can reveal the curing mechanism of the binder system in depth. [ABSTRACT FROM AUTHOR]

Sulfuric acid (SA)‐dimethylamine (DMA)‐H2O cluster formation has been proven to be responsible for a significant part of new particle formation (NPF) in a Chinese megacity. However, the possible involvement of common atmospheric acids in the subsequent growth of SA‐DMA clusters remains elusive. We simulated formation and growth of clusters using atmospheric relevant concentrations of SA, DMA, and trifluoroacetic acid (TFA), a commonly observed atmospheric perfluorocarboxylic acid, using Density Functional Theory combined with Atmospheric Cluster Dynamics Code. The presence of TFA leads to complex cluster formation routes and an enhancement of NPF rates by up to 2.3 ([TFA] = 5.0 × 106 molecules cm−3, [SA] = 1.0 × 106 molecules cm−3, and [DMA] = 1.5 × 109 molecules cm−3). The agreement of (SA)1·(DMA)1‐2·(TFA)1 concentrations between simulations and ambient measurements during NPF events validates model predictions and implies that perfluorocarboxylic acids could potentially boost atmospheric SA‐DMA NPF rates. Plain Language Summary: Atmospheric nucleation is the earliest step to form new aerosol particles, which includes a complex transformation from gaseous molecules to small clusters, then to critical clusters, and finally to freshly nucleated nanoparticles. Sulfuric acid and dimethylamine have been proved to explain atmospheric nucleation events in urban China. However, whether other atmospheric acidic species could participate in this nucleation process remains elusive. Herein, we report a sulfuric acid‐dimethylamine based nucleation mechanism with the participation of trifluoroacetic acid, a commonly observed strong acid in the atmosphere, using theoretical calculation methods. The model predictions are then validated by ambient measurements in urban Shanghai. Our results suggest that perfluorocarboxylic acids could potentially boost the formation of nanoparticles. Key Points: Theoretical simulations indicate complex atmospheric new particle formation mechanisms involving sulfuric acid, dimethylamine, and trifluoroacetic acidGood agreement of key cluster concentrations between simulations and ambient measurements during new particle formation events is obtainedTrifluoroacetic acid can participate in the growth of sulfuric acid‐dimethylamine clusters and enhance the nucleation rates [ABSTRACT FROM AUTHOR]

The design and fabrication of cathode remain a major challenge for lithium oxygen (Li‐O2) batteries. Here, RuO2/α‐MnO2 nanotubes as efficient bifunctional cathode catalysts are prepared by two‐step hydrothermal reaction to improve the battery performance. Nitrogen adsorption desorption (BET) tests indicate that RuO2/α‐MnO2 nanotubes have mesoporous structure with specific surface area of 51.2 m2 g−1. Electrochemical tests show that the catalytic activity and the conductivity of α‐MnO2 nanotubes modified with RuO2 nanoparticles are improved. RuO2/α‐MnO2 nanotubes are used as a bifunctional electrocatalyst for cathode in Li‐O2 batteries, which show reduced overpotential, improved rate and cycling performance. At the current density of 0.05 mA cm−2, the overpotential of the batteries can go down by 0.38 V, and these batteries can be fully discharged/charged 26 cycles stably at a fixed capacity of 500 mAh g−1. The combination of RuO2 nanoparticles and α‐MnO2 nanotubes has excellent catalytic activity for ORR/OER, thus greatly improving the electrochemical performance of Li‐O2 batteries. [ABSTRACT FROM AUTHOR]

The gas‐phase reaction of organic acids with SO3 has been recognized as essential in promoting aerosol‐particle formation. However, at the air–water interface, this reaction is much less understood. We performed systematic Born–Oppenheimer molecular dynamics (BOMD) simulations to study the reaction of various organic acids with SO3 on a water droplet. The results show that with the involvement of interfacial water molecules, organic acids can react with SO3 and form the ion pair of sulfuric‐carboxylic anhydride and hydronium. This mechanism is in contrast to the gas‐phase reaction mechanisms in which the organic acid either serves as a catalyst for the reaction between SO3 and H2O or reacts with SO3 directly. The distinct reaction at the water surface has important atmospheric implications, for example, promoting water condensation, uptaking atmospheric condesation species, and incorporating "SO42−" into organic species in aerosol particles. Therefore, this reaction, typically occurring within a few picoseconds, provides another pathway towards aerosol formation. [ABSTRACT FROM AUTHOR]

Abstract: The lack of systematic understanding of the effects of architecture and catalysts on the electrochemical performance of lithium‐oxygen (Li−O2) batteries hinders the rational design of air electrodes. In this work, we design and synthesize two honeycomb‐like carbon‐based architectures (HCC‐100 and HCC‐500) using a hard template method. With the same amount of Mo2C catalyst loading, the electrochemical performance is compared. At a current density of 100 uA m−2, the discharge capacity of HCC‐100@Mo2C is approximately four times higher than that of HCC‐500@Mo2C m−2. This is attributed to a higher surface area and wider mesopore distribution. Compared to HCC‐100, the material without catalyst loading, the HCC‐100@Mo2C electrode shows a considerable improvement in terms of discharge capacities, cycling stability and capacity retention. The stability of the electrode is tested with IR and SEM analysis after cycling. The SEM micrographs show that discharge products of HCC‐100@Mo2C tend to form on the catalytic site, while the discharge products of HCC‐100 tend to form a thicker layer which could lead to the increased impedance. The results of IR indicate less Li2CO3 by‐product formation with HCC‐100@Mo2C. [ABSTRACT FROM AUTHOR]

Abstract: Metal and metal oxides are considered as effective catalysts owing to their excellent oxygen reduction and oxygen evolution reaction activity. However, their low electrical conductivity, the collapse of the structure during the cycles and agglomeration in thermal treatment, which can degrade the electrochemical properties, are still puzzles for researchers. Herein, we present a facile method to synthesize mesoporous N‐doped carbon matrix modified with cobalt and cobalt oxide (Co–CoO@NC) micro‐disk derived from zeolitic imidazolate frameworks, alleviating the agglomeration of the cobalt nanoparticles to form CoO with abundant oxygen vacancies and introducing nitrogen in the carbon matrix with strong metal‐N‐doped carbon bridging bonds. The porous structure shows numerous mesoporous with diameters of 4–7 nm and an excellent specific surface area as high as 739.4 m2 g−1. The lithium‐oxygen batteries based on Co–CoO@NC electrode show improved electrochemical performance, with a high initial discharge capacity up to 5582 mAh g−1 at 0.05 mA cm−2 and preferable cycling stability with a cut‐off specific capacity of 500 mAh g−1 at 0.1 mA cm−2. The improved performance is mainly ascribed to the synergic effect of the porous structure, CoO and strong metal‐N‐doped carbon bridging bonds, leading to the excellent OER and ORR activities. [ABSTRACT FROM AUTHOR]

Bromine chemistry is responsible for the catalytic ozone destruction in the atmosphere. The heterogeneous reactions of sea‐salt aerosols are the main abiotic sources of reactive bromine in the atmosphere. Here, we present a novel mechanism for the activation of bromide ions (Br−) by O2 and H2O in the absence of additional oxidants. The laboratory and theoretical calculation results demonstrated that under dark conditions, Br−, O2 and H3O+ could spontaneously generate Br and HO2 radicals through a proton–electron transfer process at the air–water interface and in the liquid phase. Our results also showed that light and acidity could significantly promote the activation of Br− and the production of Br2. The estimated gaseous Br2 production rate was up to 1.55×1010 molecules cm−2 ⋅ s−1 under light and acidic conditions; these results showed a significant contribution to the atmospheric reactive bromine budget. The reactive oxygen species (ROS) generated during Br− activation could promote the multiphase oxidation of SO2 to produce sulfuric acid, while the increase in acidity had a positive feedback effect on Br− activation. Our findings highlight the crucial role of the proton‐electron transfer process in Br2 production; here, H3O+ facilitates the activation of Br− by O2, serves as a significant source of atmospheric reactive bromine and exerts a profound impact on the atmospheric oxidation capacity. [ABSTRACT FROM AUTHOR]

Cover Picture: Influences of Bu-NENA and BDNPA/F Plasticizers on the Properties of Binder for High-Energy NEPE Propellants (Prop., Explos., Pyrotech. Keywords: Desensitized energetic plasticizers; Binder; NEPE Propellant; Curing properties; Mechanical Properties EN Desensitized energetic plasticizers Binder NEPE Propellant Curing properties Mechanical Properties 849 849 1 06/07/21 20210601 NES 210601 B The cover image is b based on the Full Paper I Influences of Bu-NENA and BDNPA/F Plasticizers on the Properties of Binder for High-Energy NEPE Propellants i by Yalun Wang et al., https://doi.org/10.1002/prep.202000228. Desensitized energetic plasticizers, Binder, NEPE Propellant, Curing properties, Mechanical Properties. [Extracted from the article]